1. Field of the Invention
This invention relates to a fluid product dispensing pump and a fluid product dispensing device comprising such a pump.
2. Description of Related Art
Fluid product dispensing pumps are well known in the state of the art, particularly to dispense products in the cosmetic, perfume and pharmaceutical fields. They usually comprise a piston sliding in a pump body, more particularly in a pump chamber provided in this pump body, and adapted to dispense a dose of the fluid product each time that the pump is activated. The pump chamber usually comprises an inlet valve to define the product dose expelled each time that the pump is actuated. Furthermore, some pumps sometimes include closers at the dispensing orifice, particularly for pharmaceutical products to prevent any contamination of the product between two operations of the pump.
One problem that arises with this type of pump relates to priming. The first time that the pump is actuated, the pump chamber is full of air and therefore this air has to be entirely expelled so that the said pump chamber can be filled with the fluid product to enable precise and reproducible dispensing each time that the pump is actuated. Priming is made more complicated if the pump is provided with a closer. It is difficult to expel air contained in the pump chamber outside the chamber, particularly due to the presence of the said closer.
Another problem that can arise with fluid product dispensing pumps relates to the quality of the spray in the case of a spraying pump. In particular, when a closer is provided at the dispensing orifice, the quality and characteristics of the spray at the time that it is expelled depend on the said closer. Most of these closers are moved under the pressure of the product created during actuation, therefore actuations with different axial intensities or forces can change the spray characteristics. In particular in pumps in which the closer moves in the axial direction away from the dispensing orifice when the pump is actuated, an excessive displacement of the said closer can cause a loss of the spray quality and consequently bad dispensing of the dose.